<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div id="app">
    <div v-if="isShow">isShow = true</div>
    <div v-else>isShow = false</div>
</div>
<script src="../js/vue.js"></script>
<script>
    const aaa = new Vue({
        el: "#app",
        data: {
            message: "hello,guys",
            isShow: false
        }
    })
</script>
</body>
</html>